Prurigo: causes, symptoms, diagnosis, treatment

Pocessi is a heterogeneous disease characterized by the eruptions of severely itching pruriginous elements, which are papules of a dense complexion, hemispherical or conical in shape, often with a bubble on the surface, located on the edematous (urticariform) base.

Causes of scratching. It is caused by many exogenous and endogenous factors (food allergens, medicines, insect bites, etc.), is observed in many diseases of the internal organs (liver disease, leukemia, lymphogranulomatosis and other malignant processes) and CNS.

Symptoms of prurigo. It occurs paroxysmally, in most cases, ostro or subacute (infantile pruritus, prurigo acute adults Bénier, etc.), there are also chronic forms (prurigo Gebra, prurigo Dyubrya). It often develops in childhood (strobulus), but it is observed in adults both as a first-time process and persistent from childhood with temporary improvements and exacerbations. Somewhat different in clinical manifestations prurigo nodosum, characterized by the presence on the skin mainly of the lower extremities of large hemispherical papules of pale pink color, a dense consistence, covered with hemorrhagic crusts. Often with hyperkeratosis. Eruptions exist for a long time, are resistant to treatment, in their place remain hyperpigmentation, and also because of deep scratching scars. Manifestations peculiar to nodular pruritis are observed in the chronic form of phleboderma, which develops on the site of mosquito bites.

Described prurigo pigmentosa, which develops mainly in spring and summer, mainly in women, probably from rubbing with linens on the trunk, in the form of itchy red papules, sometimes located network-like. After their regression remains spotted or net pigmentation.

Pathomorphology of prurigo. In the acute form of the disease in children (infantile pruritus), the histological pattern resembles that with limited neurodermatitis, acanthosis and hyperkeratosis are expressed, and vesicles show vesicles and cortical elements in the upper parts of the epidermis. Inflammatory reaction in the dermis is small.

In acute pruritus of adults, acanthosis and spongiosis are observed in the region of the element with the formation of vesicles in the upper parts of the Malpighian layer of the epidermis, more often under the stratum corneum. In the upper third of the dermis - perivascular infiltrates from lymphocytes with an admixture of neutrophilic and eosinophilic granulocytes.

In chronic form in fresh papules - moderate acanthosis, spongiosis with the formation of small vesicles, parakeratosis. In the upper part of the dermis is a moderately expressed lymphocytic infiltrate, located mainly perivascularly. Papules with excoriation on the surface of the epidermis are covered with crusts containing decaying nuclei of infiltrate cells. At the phenomena of regeneration in the epidermis, pseudoepitheliomatous hyperplasia with unevenly expressed zidermal processes can develop. In the dermis in such cases, the inflammatory infiltrate is expressed significantly.

With nodular pruritis, pronounced acanthosis and hyperkeratosis are noted, sometimes papillomatosis with uneven proliferation of epidermal outgrowths. It is often possible to observe hyperplasia of skin nerves and neurolematocytes, as well as fibrosis of the dermis. When electron microscopy finds outgrowths of axons and neyrolemocytes, dystrophic changes in nerve structures in the form of axon swelling. Differentiate the disease from keratoacanthoma and other diseases accompanied by pseudospiteliomatous hyperplasia. It should be noted that the histological picture can be indistinguishable from changes in atopic dermatitis and limited neurodermatitis. In such cases, the correct diagnosis is marked by clinical data.

[1], [2], [3], [4], [5], [6], [7]